If you're one of those people who has trouble in class because you're constantly distracted by your phone, this app might help. I recently discovered an app called Forest, which grows a tree as you engage in focused work. When you leave the app, the tree dies. If you engage in focused work over time, you grow a forest, and the group behind the app plants real trees around the world. It's a neat way to keep your hands off your phone, as you keep your tree growing.